1. Field of the Invention
The present invention relates to an image forming apparatus in which a toner image is formed on an image bearing member where a latent image has been formed by an exposure device and the toner image is transferred to a recording material. More particularly, the present invention relates to an apparatus that forms a marginless image on a recording material.
2. Description of the Related Art
An apparatus having a sensor that detects edges of a recording material before a point where an image is transferred to the recording material is a known structure to form an image at a satisfactorily precise position on a recording material. For example, Japanese Patent No. 3,848,147 discloses a structure for detecting an edge of a recording material in a recording material conveying direction and an edge of the recording material in a direction orthogonal to the recording material conveying direction with an image sensor being placed at a point upstream of the transfer point along a recording material conveying path. An image forming apparatus disclosed in this related art example attempts to improve the precision of the image formation position by detecting edges of a recording material before the transfer point and adjusting when to form an image based on this detection information.
However, the above-mentioned image forming apparatus adjusts a timing of forming an image based on information about the recording material position detected before the transfer point. The precision of the image formation position of the image forming apparatus disclosed in the above-mentioned related art example can be low when the curling, rippling, or the like of a recording material produces fluctuating results in recording material edge detection, or when there is an error in distance from a point where the sensor detects the edges to the transfer point or an error in recording material conveying speed.